题目

 When you watch TV programs about wild animals, it is surprising to see how an antelope can escape a lion’s attack. In the wilderness, everyone has a stunt(绝招). Even plants have their own ways of fighting off enemies. Over millions of years of evolution(进化), plants have developed a unique defence system. Chemicals are widely used for survival. By making their leaves, flowers, roots and fruits poisonous to enemies, plants can fight back. One such plant is the Golden Wattle tree, British scientist David Caneron has found when an animal eats the tree’s leaves, the amount of po19．如图1，在平面直角坐标系中，抛物线y=-$\frac{\sqrt{3}}{4}$x2+$\sqrt{3}$x+3$\sqrt{3}$交x轴于A，B两点（点A在点B的左侧），交y轴于点W，顶点为C，抛物线的对称轴与x轴的交点为D．（1）求直线BC的解析式；（2）点E（m，0），F（m+2，0）为x轴上两点，其中2＜m＜4，EE′，FF′分别垂直于x轴，交抛物线于点E′，F′，交BC于点M，N，当ME′+NF′的值最大时，在y轴上找一点R，使|RF′-RE′|的值最大，请求出R点的坐标及|RF′-RE′|的最大值；（3）如图2，已知x轴上一点P（$\frac{9}{2}$，0），现以P为顶点，2$\sqrt{3}$为边长在x轴上方作等边三角形QPG，使GP⊥x轴，现将△QPG沿PA方向以每秒1个单位长度的速度平移，当点P到达点A时停止，记平移后的△QPG为△Q′P′G′．设△Q′P′G′与△ADC的重叠部分面积为s．当Q′到x轴的距离与点Q′到直线AW的距离相等时，求s的值．